How to conceive with irregular periods?

My husband and I have been trying to conceive for 9 years, however my cycle is terrible! 3-4x a year. They last the average 7-10 days when I do get them. My gyno told me there was no reason I wouldn't be able to but I'm having my doubts still. Is there anything you guys know that could help me?

And I don't know if it's relevant but during an ultrasound she did state my womb was large but didn't go into details on why or what it meant even though I should have asked but don't know why I didn't.

Thanks!